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HVAC heating seems weak.

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Old 01-19-2023, 01:53 PM
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Speedtoys
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Default HVAC heating seems weak.

I have all good working vacuum pods, and a good working heater valve under the hood.

But..aside from the central vent never feeling warm (the side and floor vents seem to operate just fine)...when its COLD, and heater is all the way up, it's no where near as hot as I believe it should be.

Where do I start looking?

I thought I had the mixer motor properly set for the A/C, and I know that me head unit and ambient temp inputs both work fine as well.
Old 01-19-2023, 03:20 PM
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Zirconocene
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Have you tried a higher temperature thermostat?
Old 01-19-2023, 03:39 PM
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Originally Posted by Zirconocene
Have you tried a higher temperature thermostat?
haha...I dont think that's what's broken Doctor.

Old 01-19-2023, 03:52 PM
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Kevin in Atlanta
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I'd start with the setting motor. You can check to see if you get full movement while you slide the temp slider.

It's above your knee.

Could be a problem with temp sensor, too.

Last edited by Kevin in Atlanta; 01-19-2023 at 03:54 PM.
Old 01-19-2023, 05:21 PM
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soontobered84
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The passenger footwell flap could be leaking cold air into the hot air mix from the heater.
Old 01-19-2023, 06:45 PM
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davek9
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Curious, what exactly are the measured Temps of the Engine, center, side and floor ?
Also note that an old Heater valve can look like it's working however the "O" ring inside can become dislodged, blocking flow.

Thanks,

Dave K
Old 01-19-2023, 06:48 PM
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Originally Posted by davek9
Curious, what exactly are the measured Temps of the Engine, center, side and floor ?
Also note that an old Heater valve can look like it's working however the "O" ring inside can become dislodged, blocking flow.

Thanks,

Dave K
Valve is 5mo old, I see it working, the floor recirc vent closes and opens correct, was recently in there too..

Id have to wait a week or two to get operational temps (in body shop).
Old 01-19-2023, 07:00 PM
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Yes actual temps will help diag the issue, good to know the other bits have been verified

Dave K



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